The Chevrolet Volt is a plug-in series
hybrid vehicle to be produced by General Motors, expected to be launched as
a 2011 model with production currently slated to begin in 2010. The Volt's
propulsion system will be based on GM's new E-Flex platform.

Unlike current commercially available hybrids, the actual propulsion of the
Volt is accomplished by the electric motor, as the internal combustion
engine (ICE) is not mechanically connected to the wheels. With fully charged
batteries, this electric power may be sourced exclusively from its onboard
lithium-ion batteries, for up to 40 miles, a distance capable of satisfying
the daily commute of 75% of Americans, which averages around 33 miles.

After 40 miles, the range of the Volt will need to be extended through the
use of a small 4-cylinder ICE which drives a 53 kW generator. The electrical
power from the generator is then sent to either the electric motor or the
batteries, depending on the state of charge (SOC) of the battery pack and
the power demanded at the wheels. The distribution is controlled by the
electronic control unit (ECU) of the vehicle. This effectively extends the
Volt's potential range to as much as 640 miles on a single tank of fuel
(which could be potentially extended for longer trips through conventional
refueling).

The Volt's 16 kWh lithium-ion battery pack can also be fully charged by
plugging the car into a 120-240VAC residential electrical outlet using the
provided SAE J1772 compliant charging cord. No external charging station
will be required.

Since the current Society of Automotive Engineers (SAE) definition of a
hybrid vehicle states the vehicle shall have "two or more energy storage
systems both of which must provide propulsion power, either together or
independently",the company has avoided the use of the term "hybrid" when
describing its non-conforming E-Flex designs. Instead GM has described the
Volt as an electric vehicle equipped with a "range extending" gasoline
powered internal combustion engine (ICE) as a genset and therefore dubbed an
"Extended Range Electric Vehicle" or EREV. However, the combination of an
internal combustion engine and electric motors in such a configuration is
most often referred to as a series hybrid.